These articles represent the follow-up (the scientific data) to the GEITP email of October 16th [see far below]. How does the same DNA sequence, present in virtually every cell in the body, give rise to diverse tissues that have distinct functions? The Genotype-Tissue Expression (GTEx) Consortium aims to answer this question by using a strategy called expression quantitative trait loci (eQTL) mapping. This technique allows the researchers to generate a comprehensive catalog of associations between genetic variation and gene expression across many tissues in many individuals.

In the attached articles in the first email and Part II in this email (because the total size of all the articles is too large for some colleagues’ server to accept), the consortium presents the second phase of their project, and the largest survey of this type to date. Over the past two decades, considerable progress has been made toward understanding the molecular mechanisms that underlie dynamic gene-regulatory programs that control development, differentiation, and function in specific cell types. The outstanding challenge is to understand, and ultimately to predict, how genetic differences between individuals contribute to specific multifactorial traits –– including susceptibility to disease and drug efficacy and toxicity.

A large body of work has shown that genetic variants that drive inter-individual differences in complex traits are often found in non-protein-coding regions of the genome that might determine how and when genes are expressed. As a result, biologists have set out to catalog and understand how genetic variation in both coding and non-coding regions affects dynamic and tissue-specific gene-expression programs. The GTEx project, initiated in 2010, represents a coordinated attempt to begin to achieve this goal.